The SRAM issue:On the IO_MUX page where is the address and data pins for a SRAM chip? How do I tell the memory controller?Am I not looking in the right PDF?

I just downloaded everything earlier this morning and now you've pointed to version 1.1 !Update: The link points to a page where the labels have rev numbers but the documentation is the same.Can you throw me a hint which PDF contains the description on GPIO Mapping?Thanks

The SRAM issue:On the IO_MUX page where is the address and data pins for a SRAM chip? How do I tell the memory controller?Am I not looking in the right PDF?

I just downloaded everything earlier this morning and now you've pointed to version 1.1 !Update: The link points to a page where the labels have rev numbers but the documentation is the same.Can you throw me a hint which PDF contains the description on GPIO Mapping?Thanks

SPIRAM:MR25H40MDF 4M as 512KX8 $21.82 qty 1Earlier I had read we could add external SRAM as IRAM... I don't think so, maybe after it's moved into IRAM but this SPIRAM stuff is painful to work with. It has 1 byte writes, after you set it up and 40 clock cycles later your done. I could see it as a buffer to save the flash from being over used, maybe chaining DMA to the SPI....Interesting -> http://www.computerworld.com/article/30 ... vices.html

For now, external SRAM is only really usable by either using it as a generic external SPI device or by using a SPI channel with DMA to essentially copy data to or from it. In theory, we also have a way to map 4MB of SRAM into into the D-bus (so you can basically use it in the same way as you can use DRAM that is inside the ESP32) but there's something funny going on with that; it'll probably cost us 2 to 3 months to fix this.

ESP_Sprite wrote:For now, external SRAM is only really usable by either using it as a generic external SPI device or by using a SPI channel with DMA to essentially copy data to or from it. In theory, we also have a way to map 4MB of SRAM into into the D-bus (so you can basically use it in the same way as you can use DRAM that is inside the ESP32) but there's something funny going on with that; it'll probably cost us 2 to 3 months to fix this.

Keep us upto date! The ESP32 is perfect for my application save for my SRAM requirement.

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